Filler reinforcing means and guard for mechanical pencils



Oct. 19, 1948. J. L. MORTON FILLER REINFORCING MEANS AND GUARD FORMECHANICAL PENCILS Filed 001; 5 1946 INVENTOR cibhizlJibrion R- 30mmAGENT Patented Oct. 19, 1948 FILLER REINFORCING MEANS AND GUARD FORMECHANICAL PENCILS John L. Morton, Endicott, N. Y., assignor toInternational Business Machines Corporation, New York, N. Y., acorporation of New York Application October 5, 1946, Serial No. 701,501

4 Claims. 1 The present invention relates to mechanical re.- fillablelead or crayon holders of the type commonly known as mechanical pencilsand in which the graphite or other writing stick, crayon, lead or filleris adapted to be projected from or withdrawn into the body of the holderby a screw-- feed action occasioned by relative turning movement betweenthe body portion of the writing implement and the eraser-retaining orother cap or head.

Heretofore, writing implements of this type have possessed one seriouslimitation, to wit, that unless extremely light pressure is applied tothe writing surface by the point of the crayon stick or filler, thelatter is subject to breakage. This extremely annoying phenomenon is dueto the fact that the filler, being formed of pressed graphite or similarcompound, is inherently relatively fragile and britle and, if the samebe projected from the end of the surrounding ferrule an appreciabledistance, the bending torque at the point of entry of the filler duringnormal use of the implement is sufficiently great as to cause theprojecting portion of the filler to break off from the remainder of theencased filler. Such rupture of the filler is occasioned by acombination of factors, principal among which are the relatively sharpslant or angle of incidence between the filler and the writing surfacewhich is convenient to and preferred by most users of such implements,and the degree of writing pressure applied to the writing surface.

Another limitation that is attendant upon the use of mechanical pencilsof the type set forth above is the necessity of withdrawing the fillerinto the body of the holder after each use thereof to prevent accidentalbreakage of the filler in the pocket of the user, as well as to preventthe clothing from becoming soiled due to repeated contact with thefiller proper.

The present invention is designed to overcome the above notedlimitations that are attendant upon the use of mechanical pencils of thetype outlined above and, toward this end, contemplates the provision ofa metal or other reinforcing sheath which surrounds the filler and whichis slidably disposed within the bore of the ferrule and is yieldinglymaintained in a projected position wherein it completely surrounds andconceals the projected portion of the filler and thus reinforces thelatter and prevents the same from damage. The reinforcing sheath isadapted to be automatically and telescopically retracted into the bodyof the ferrule so as to expose only the immediate end of the projectedportion of the filler upon application of writing pressure to the writ-;ing surface. Upon withdrawal of the writing pressure by lifting of theimplement from the writing surface, the sheath is adapted to return toits normal protective position relative to the filler. In this mannerthe filler is protected against rupture upon application of writingpressure to. the writing surface, as well as being protected fromaccidental breakage, such as is frequently the case when the implementis carried in the pocket of the user. Additionally, the clothing of theuser is protected from becoming soiled due to contact with the fillerproper. V

The provision of a mechanical pencil of the character briefly outlinedabove being the prin-. cipal' object of the invention, another objectthereof is to provide a protecting means for the filler which will in nomanner interfere with the normal feeding movements of the implement andwhich will require no modification in the design or constructionthereof.

Simplicity, convenience of arrangement of parts, ruggedness anddurability and comparative low cost of manufacture are furtherdesiderata I that have been borne in mind in the production anddevelopment of the present invention.

' In the accompanying single sheet of drawing forming a part of thisspecification:

Fig. 1 is a fragmentary side elevational view, partly in section, of amechanical pencil constructed in accordance with the principles of thepresent invention.

Fig.2 is a sectional view taken substantially longitudinally andcentrally through the lower regions of the pencil. In this view, theconventional spiral filler or crayon feeder, as well as certain otherparts, have been removed to more clearly reveal the nature of theinvention.

Fig. 3 is a sectional view, similar to Fig. l, showing a modified formof mechanical pencil.

Fig. 4 is a view, similar to Fig. 1, showing the pencil in actual use.

Referring now to Figs. 1, 2 and 4, the pencil involves in its generalorganization an outer shell or casing H3 which is shown in outline onlyby means of broken lines. Fitted within the lower tapered end of theshell i0 is a hollow tapered metal ferrule l2 having a central bore l4through which the crayon stick or filler proper I5 projects and fromwhich it is adapted to be projected at will by means of a conventionalfeeding mechanism.

The ferrule I2 is provided with a reduced portion l8 which istelescopically received within the bore of the shell I0 and maintainedtherein by 3 means of a tight frictional fit so that when the pencil isin actual use these parts are, in effect, as one and are possessed of norelative turning movement therebetween.

The feeding mechanism includes an elongated guide sleeve 20 which is butslightly shorter than the overall length of the pencil and the lower endof which is securely held by a friction fit or otherwise in the upperportion of the bore I4 of the ferrule I2. In the regions of the sleeve20 above the ferrule the former is slotted as at 22 throughout a majorportion of its length, one edge of the slot appearing in the drawing inelevation throughout the various views. A filler retainer and feeder isslidably disposed within the bore of the sleeve 20 and includes a secondslotted sleeve 24 of small diameter into the lower end of which theupper end of the filler I is telescopically received and held by a lightfrictional fit. The medial regions of the inner sleeve 24 is formed witha lateral protuberance 26 which projects outwardly through the slot 22of the sleeve 20. An ejecting pin 28 is slidably disposed within theinner sleeve retainer 24 and is provided with a laterally turned upperend 30 which projects through the slot 32 in the inner sleeve and theslot 22 of the outer sleeve 20.

The protuberance formed by virtue of the laterally turned end 3|] of theejecting pin 28 and the protuberance 26 formed on the retainer sleeve 24are adapted to be received in adjacent convolutions of a conventionalspiral feeder 34 which appears in Figs. 1 and 4 but which has beenomitted from Fig. 3 for the sake of clarity of disclosure. The feeder 34is adapted to receive on its upper end a suitable eraser-retaining capor head (not shown) by means of which it may be turned relative to theshell and ferrule assembly III, I2.

It will be seen that turning movement of the spiral feeder 34 in onedirection or the other will cause the retainer sleeve 24 and ejectingpin 28 to slide upwardly or downwardly, as the case may be, within thebody of the guide sleeve while these two parts maintain their relativepositions with respect to each other. However, when the spiral feeder 34is turned in such a direction and to an extent sufficient to cause thelower protuberance 26 to leave the convolute path in which it is guided,it will cease to have motion, while the upper protuberance will continueto descend in its spiral path, carrying with it the body portion of theejecting pin 28 which will thus force the filler from its frictional fitwithin the retainer sleeve 24. It will, of course, be understood thatduring turning movement of the spiral feeder 34 in one direction or theother the filler I5 will be fed outwardly from or withdrawn into thebody of the pencil.

The arrangement of parts described above is purely conventional in itsdesign and no claim is made herein to any novelty associated with thesame, the novelty of this invention residing rather in the constructionand arrangement of parts now to be more fully described and claimed.

Loosely slidable within the bore I4 of the ferrule I2 is a reinforcingsleeve 50, the internal diameter of which is slightly greater than theexternal diameter of the filler I5 and the external diameter of which isslightly less than the internal diameter of the bore I4. The sleeve isthus freely slidable in a vertical direction longitudinally of thepencil relative to both the :filler and the ferrule and is capable ofbeing projected from or retracted into the latter. In Fig.

2 it is shown in its fully projected position and in Fig. 4 it is shownas being retracted.

The upper end of the sleeve 50 is provided with a laterally turned lug52 which projects outwardly through the slot 22 formed in the guidesleeve 20. This lug 52 determines the limiting or fully projectedposition of the sleeve 50. A coil spring 54 of relatively lightconstruction surrounds the lower end of the guide sleeve 20 and bears atits lower end against the upper end of the reinforcing sleeve 50. At itsupper end the spring 54 bears against the underneath side of a Washer 56which in turn bears against the lower end of the spiral feeder 34.

From the above description it will be seen that normally the reinforcingsleeve 50 is maintained in its projected position as shown in Fig. 2wherein the lower end and writing point of the filler I5 is completelyconcealed from view and sheathed from contact with the clothing of theuser when the pencil is carried on his person. With the parts in thisposition, the filler is not subject to accidental damage, while at thesame time the clothing of the user is protected from contamination.

When the pencil is applied to a writing surface in the usual manner, asillustrated in Fig. 4, gentle pressure of the lower end of the implementagainst the writing surface will cause the reinforcing sleeve 50 to bepushed back into the ferrule to an extent just sufficient to expose thewriting point of the filler I5. In this manner, any torque which wouldordinarily be applied to the filler in a direction normally tending tocause breaking of the latter will be borne by the reinforcing sleeve andthe filler will be protected against breakage.

In Fig. 3 a modified form of the invention is illustrated. In this viewsimilar reference characters have been applied to those parts whichcorrespond to similar parts in the other views to thus avoid repetitiousdescription.

In the modified form of Fig. 3, the reinforcing sleeve I50 isconsiderably shorter than the sleeve 50 in the other form of theinvention and is provided with an annular lug I52 at its upper end whichnormally rests at the bottom of an enlargement III formed in the bore II4 of the ferrule II 2. The spring I54 is wholly disposed within theenlarged portion II! of the bore and its upper end bears against awasher I56 which in turn bears against the lower end of the spiralfeeder I34. In this form of the invention the spiral feeder I34 extendsto a point close to the upper end of the ferrule II 2,

The invention is not to be limited to the exact arrangement of partsshown inthe accompanying drawing or described in this specification asvarious changes in the details of construction may be resorted towithout departing from the spirit of the invention. For example, whilethe protective and reinforcing sleeve 50 has been shown as beingincorporated with a mechanical pencil which operates upon the spiralfeeder principle, obviously the same may be employed in connection withother types of mechanical pencils employing feeding means other thanthose controlled by a spiral element such as that shown at 34 herein.Additionally, while the element I5 herein'has been termed a crayon orlead the definition herein intended is applicable to writing elementsformed of pressed graphite, graphite compounds and other variouslycolored compositions commonly grouped in the art and included under theterm fillers. Only insofar as the invention has particularly beenpointed out in the accompanying claims is the same to be limited.

What is claimed is:

1. In a mechanical pencil of the character de' scribed, a ferrule havinga central bore extending therethrough, a crayon stick disposed in saidbore, means for feeding said stick to project the same from or towithdraw the same into said ferrule, a reinforcing sleeve slidablydisposed in said bore and surrounding said stick and movable from anadvanced position wherein a relatively short length thereof projectsbeyond the end of said ferrule to a retracted position wherein it issubstantially fully withdrawn into the latter, and means yieldinglymaintaining said sleeve in its advanced position, said sleeve beingadapted when the crayon stick is projected a slight distance beyond theend of said ferrule to substantially conceal the stick and to become atleast partially retracted against the action of said yielding means toexpose the writing point of the stick when writing pressure is appliedto a writing surface by the writing end of the pencil.

2. In a mechanical pencil of the character described, a ferrule having acentral bore extend-- ing therethrough, a crayon stick disposed in saidbore, means for feeding said stick to project the same from or towithdraw the same into said ferrule, a reinforcing sleeve slidablydisposed in said bore and surrounding said stick and movable from anadvanced position wherein a relatively short length thereof projectsbeyond the end of the ferrule to a retracted position wherein it issubstantially fully withdrawn into the latter, and a coil spring bearingagainst said sleeve and normally urging the latter to its advancedposition, said sleeve being adapted when the crayon stick is projected aslight distance beyond the end of the ferrule to substantially concealthe stick and to become at least partially retracted against the actionof said spring toexpose the writing point of the stick when writingpressure is applied to a writing surface by the writing end of thepencil.

3. In a mechanical pencil of the character described, a ferrule having acentral bore extending therethrough, a guide sleeve having an endthereof secured in said bore, said sleeve and ferrule being disposed inconcentric relationship, a crayon stick extending completely throughsaid bore and projecting into said guide sleeve, means associated withsaid guide sleeve for feeding said stick to project the same from orwithdraw the same into said ferrule, a reinforcing sleeve slidablydisposed in said bore and surrounding said stick, said reinforcingsleeve being normally freely movable relative to the ferrule and stickfrom an advanced position wherein a relatively short length thereofprojects beyond the end of the ferrule to a retracted position whereinit is substantially fully withdrawn into the latter, and a springsurrounding said guide sleeve and bearing against said other sleeve andnormally maintaining the latter in its advanced position, said lattersleeve being adapted when the crayon stick is projected a slightdistance beyond the end of the ferrule to substantially conceal thestick and to become at least partially retracted against the action ofsaid spring to expose the writing point of the stick when writingpressure is applied to a writing surface by the writing end of thepencil.

4. In a mechanical pencil of the character described, a ferrule having acentral bore extending therethrough, a crayon stick disposed in saidbore, means for feeding said stick to project the same from or towithdraw the same into said ferrule, a reinforcing sleeve slidablydisposed in said bore and surrounding said stick and movable from aposition wherein a relatively short length thereof projects beyond theend of the ferrule to a retracted position wherein said projectinglength is substantially fully withdrawn into the ferrule, saidreinforcing sleeve being disposed substantially wholly within said bore,a flange formed on said reinforcing sleeve, a spring surrounding saidreinforcing sleeve and having one end thereof bearing against saidflange to normally urge the sleeve to its advanced position, said sleevebeing adapted when the crayon stick is projected a slight distancebeyond the end of the ferrule to substantially conceal the stick-and tobecome at least partially retracted against the action of said spring toexpose the writing point of the stick when writing pressure is appliedto a writing surface by the writing end of the pencil.

JOHN L.. MORTON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,005,485 Wells June 18, 19352,063,637 Stossel Dec. 8, 1936

